Firearm



C. C. LOOMIS June 5, 1945.

FIREARM 5 Sheets-Sheet 1 Filed April 28, 1945 mmvrozm C/iA WFORD CLoo'M/s BY z 2 f June 5, 1945. c (3, LOOMIS 2,377,703

FIREARM Filed April 28, 1943 3 Sheets-Sheet 2 C. C. LOOMIS June 1945.

FIREARM Filed April 28, 1945 3 Sheets-Sheet 3 INVENTOR C'RA WFO/FD C LOO/W6 Patented June 5, 1945 FIREARM Crawford 0. Loomis, Ilion, N. Y., assignor to Remington Arms Company, Inc., Bridgeport. Conn., a corporation oi. Delaware Application April 28, 1943, Serial No. 484,808

8 Claims.

This inventionrelates, ingeneral, to firearms, and, especially to an autoloading rifle havinga transversely swinging breech block and a gas operated slide for actuating the breech block.

An object of the invention is to provide an autoloading firearm with improved means to enable primary extraction of a fired cartridge case. A further object is to provide an autoloading rifle with a transversely swinging breech block and a cartridge ejector associated therewith for enabling simultaneous transverse and longitudinal movement of the breech block. A still further object is to provide an autoloading rifle having a gas operated slide and a fore-end constructed and arranged to enable manualoperation of the slide. is to provide a firearm with means for selectively A still further object converting it from a gas operated firearm to a manually operated firearm.

Other objects, features and advantages of the invention will be more specifically described in the following specification and accompanying drawings which illustrate one exemplary embodiment of the invention. It will be understood, however, that the invention is not limited thereby but includes all modifications within the scope of the appended claims.

In the drawings: Fig. 1 shows a side elevation of the assembled gun.

receiver of the gun of Fig. 1 showing the breech block locked in breech closing position.

Fig. 2a is a plan view partly in section of the receiver of the gun of Fig. 1 showing the breech block retracted.

Fig. .3 is a side view partly in sectionshowing the firing pin freed from the slide for forward movement by the hammer.

Fig. 4 is a side view partly in section showing the breech block fully retracted in the receiver and the firing pin moved into retracted position therein by the slide.

Fig. 5 is a cross sectional view of the receiver and breech block on line 55 of Fig. 3.

6 is a top plan view of the breech block showing the cartridge ejector in its normal retracted position.

Fig. '7 is -a bottom view of the breech block shown in Fig. 6.

Fig. 8 is a front end view of the breechblock shown mounted on the slide.

Fig. 9 is a rear end view of the breech block.

Fig. 10' is a plan view of the slide including a pair of slide arms.

Fig. 11 is a sideelevation partly in section of the gun barrel of Fig. 1 and the gas operated slide actuating mechanism associated therewith.

Fig. 12 is a plan view partly in section of the gas piston and slide operating cross head.

Fig. 13 is a perspective view of the piston rod and yoke showing the finger grips.

Fig. 14 is a transverse view in section on line 14-44 of Fig. 11.

Fig. 15 is a transverse view in section on line l5-l5 of Fig. 12.

Fig. 16 shows a modification of the gun shown in Fig. 1.

* The firearm of this invention, as shown in Figs.

1 and 16, is convertible selectively from a gas operated gun having a fixed fore-end to a gun having a manually operated fore-end.

,Referring first to the gas operated model shown in Fig. 1, the firearm comprises a barrel i5 suitably mounted on a receiver, indicated generally at It, having a top wall ii and side walls l8 and I9 which house the breech closing block, indicated generally by the numeral 20. Cartridges are fed to chambering position from a suitable box magazine 22 of any well known type removably secured by a yielding magazine lock in an opening 23 in the bottom of the receiver. To the rear of the magazine is a fire control mechanism, indicated generally at 24, which comprises the triggerplate 25- removable as a unit from the opening 23 of the receiver. A substantially similar fire control mechanism is shown in the patent to Crawford C. Loomis, No. 2,039,814, May 5, 1936, and forms no part of the present invention.

In the present embodiment, however, improved means are provided for securing the trigger plate unit '25 in the aperture 23 of the receiver and comprise forwardly extending cars 26, see Figs. 3 and 4, one on each side and at the front end of the trigger plate 25 and adapted to seat in suitable recesses 21 on the inside of the walls i8 and is of the receiver. Thus, the complete trigger mechanism may be assembled in its entirety in the receiver simply by first inserting the ears 28 of the trigger plate 25 in their respective recesses '27 and then swinging the plate clockwise about these ears until the rear end 25' of the trigger plate seats securely in the bottom aperture of the receiver. A single pin 28, driven through. aligned holes in the walls of the receiver and trigger plate is suflicient to hold the unit in assembled position in the receiver.

A substantially rectangular aperture 29 is suitably formed in the right hand wall ll of the receiver for enabling ejection of the fired cartridge case as hereinafter described.

Receiver Referring to Figs. 1 through 4, the receiver i6 is shown secured to the firearm stock 30 by means of a draw bolt 32 which extends from the butt of the stock (not shown) forwardly through the pistol grip portion 33 into a threaded hole 34 in the rear end 35 of the receiver. The abutting surfaces of the pistol grip and rear wall 35 of the receiver are substantially fiat and a recess 23' is provided in the bottom of the pistol grip 33 forming an extension of the aperture 23 in the bottom of the receiver for accommodating the rear end 25' of the trigger plate 25.

The front end of the receiver is provided with a front wall 33 having a threaded hole 31 for securing the screw threaded end of the barrel l to the receiver. Directly beneath the threaded hole 31 is a smooth bored cylindrical recess or socket 36 adapted to receive the rear endof a gas cylinder 39 as shown in Figs. 11 and 12 and hereinafter described.

Milled or otherwise formed on the inside of each wall l8 and IQ of the receiver is a longitudinal recess 40, see Fig. 5, providing a shoulder 42 which extends from the front wall 36 of the receiver rearwardly to the front wall 43 of the trigger plate 25. As shown in Figs. 3 and 4, each shoulder 42 of the receiver is in substantially the same horizontal and vertical plane of the adjacent top edges 44 of the sides of the trigger plate so that the shoulders 42 and edges 44 constitute, in eflect, a continuous longitudinally extending rail for slidingly supporting the reciprocating breech block and slide mechanism shown in detail in Figs. 6 through 9.

Action mechanism Referring to Figs. 6 and '7, the breech block, indicated generally at 23, comprises a substantially rectangular block having a front end 45 which makes a slight angle with respect to the parallel side walls of the block. At its rear end 46, the block is formed with a vertical notch 41 in one corner and comprises a cam surface 48 for the purpose hereinafter described. Suitably formed in the left side of the block, see Fig. 9, is a longitudinally extending substantially rectangular recess 49 which is of substantially uniform depth throughout the length of the breech block except at its forward end where the depth of the recess is increased to provide a pocket 50, as indicated by the dotted line in Fig. 6. A narrow longitudinally disposed groove 52 is milled or otherwise cut in the bottom of the pocket 50, as shown in Figs. 6 and 8..

At a point substantially one-third the length of the breech block from its front end and intersecting the longitudinal recess 49 is a transverse slot 53, the front and side walls of which are substantially at right angles and parallel respectively to the sides of the breech block. The rear end 54 of the recess is inclined as shown and constitutes a camming surface.

The longitudinal recess 49 is adapted to support the cartridge ejecting means or cartridge ejector which comprises a fiat metal strip 55 substantially rectangular in cross section, somewhat longer than the breech block, and substantially equal in thickness to the depth of the recess 49 throughout a major portion of its length. The front end of the ejector is, however, of increased thickness corresponding to the depth of the pocket 56 and is provided with a downwardly projecting rib 53 adapted to seat in the groove 52 of the pocket 50. As shown in Figs. 6 and 8, a, suitable notch 51 is cut in the forward inside corner of the rib portion 56 of the ejector. Welded or otherwise secured to the ejector at a point thereon substantially opposite the slot 53 of the breech block is a laterally projecting lug 58 suitably proportioned with relation to the slot 53 so as to be movable forwardly therein and provided with an oblique or cam surface 59 adapted normally to be held in contact with the cam surface 54 of the breech block by means of a resilient fastening means. The latter comprises a coil spring seated in a hole drilled at an angle in the breech block and a spring pilot 62, the forward .end of which projects into the hole of the breech block while its rear end is engaged in a recess in the lug 58 of the ejector 55. In its normal position in the breech block, both the rear end 55' of the ejector and its front endproject beyond the respective rear and front faces of the breech block.

On the opposite side of the breech block at its front end is provided a well known type of cartridge extractor 63 which is pivotally supported in a recess in the side of the block and held in normal position by suitable resilient means (not shown).

A substantially vertical U-shaped recess 64 is provided in the front face of the breech block for seating the head of the cartridge case, the latter being held therein by engagement of the extractor with the rim of the case.

A firing pin 65, see Figs. 2 through 4, is slidably supported in a longitudinal slot 66 in the top of the breech block. This slot extends from a point substantially in the center of the block adjacent it front end 45 rearwardly, at a slight angle to the longitudinal axis of the breech block, to the rear end 48 of the breech block.

At the front end of the slot 66 and adjacent the bottom thereof is provided a drilled aperture 61 which passes through the front end of the block into the recessed face 64 and is adapted to accommodate the striking element 68 of the firing pin 65 as clearly shown in Fig. 3. Substantially two-thirds way back in the slot 66 and in the bottom thereof is formed an elongated aperture 69 adapted to receive a. depending finger 16 of the firing pin 65, the finger 10 being displaceable longitudinally in the elongated slot 69 from its normal rearward position, as shown, to its firing position in the manner hereinafter described. The bottom of the firing pin slot 66 is shown deepened at its rear end to provide a bear ing surface 12 on which is adapted to ride the enlarged tail-end portion 13 of the firing pin. In accordance with this construction, the firing pin contacts the bottom of the slot 66 at substantially two points only, namely, at its tail-end l3 and at a point adjacent the striking element 68. The firing pin is provided at its rear end with an anvil portion 14 which, in the normal or retracted position of the firing pin in the breech block, extends rearwardly of the rear end thereof as shown in Figs. 3 and 4.

To provide clearance for the rearwardly projecting end of the firing pin when the breech block has been moved to its rearmost position in the receiver, a suitable recess 15 is formed in the rear wall 35 of the receiver. The upper edge of the firing pin is provided at each end with a bearing surface I6 and 11 respectively for slid- I 2,377,703 ingly engaging the unlierside of the top wall I! I of the receiver.

On the bottom of the breech block, see Fig. 7, is a downwardly projecting lug 18 which is substantlally in the center of the block adjacent its front end and comprises a rectilinear member having concave sides 19 terminating in rounded shoulders 80. A second substantially disk-shaped lug 82 is' formed on the bottom of the breech block adjacent its rear end and is laterally displaced slightly with respect to the longitudinal axis of the breech block.

Referring to Figs. 8, 9 and 10, the breech block is shown mounted on a slide 83 which comprises a substantially U-shaped sheet metal member having side walls 84 and 85 and a top surface 86. Each side wall is cut out at its forward end to form a hook-shaped element s11, see Fig. 4, which is adapted to engage a correspondingly shaped hook at the rear end of the slide action bars hereinafter described. The top as of the slide is provided at its forward end with an open substantially rectangular slot t8, the parallel sides of which are slightly arcuate, as shown in Fig. 10, and adapted to slidingly engage the sides is and rounded shoulders at of the lug it on the bottom of the breech block when the slide and breech block are assembled.

In their assembled position, the disk-shaped lug 8'2 of the breech block projects into an arcuate shaped aperture 89 in the rear end of the slide, the width of the aperture corresponding substantially to the diameter of the disk-shaped lug 82, whereby the latter makes a smooth run-- ning fit therein. Extending forwardly from the periphery of the aperture at is arecess 9t milled or otherwise formed in the top of the slide 83 and of a depth sumcient to enable the end of the firing pin finger it to move forwardly from the areuate aperture 89 into the recess til, as shown in Figs. 3 and i.

A shoulder 92 formed at the forward end of the recess 98 is adapted to be engaged by the end of the finger it to provide a positive retracting means and stop for the firing pin. Thus, when the breech block is in its forward breech closing position in the receiver and the slide has been moved forwardly relative to the breech block in the manner shown in Fig. 3, the finger '50 of the firing pin will be free to move forwardly from the arcuate slot 39 into the recess 96. Consequently, when the hammer 93 is released and strikes the anvil portion it of the firing pin, its striking element 68 is enabled to move forwardly through the aperture 8? and penetrate the rimer cup of a cartridge case.

When the breech block and slide are moved into their retracted position, as shown in Fig. i, the slide 83 will have been moved relative to the breech block 2E0 so that the shoulder 92 of the recess 9t engages the finger iii of the firing pin and positively retracts the firing pin in its slot 66, thereby withdrawing the striking elements 68 from the recessed face 64 of the breech block; moreover, the shoulder 92 constitutes a stop prohibiting any forward movement of the firing pin in the breech block until such time as the latter is again locked in its forward breech closing position.

The breech block 20 is moved back and forth in the receiver by means of the slide 83 which in turn is actuated by reciprocation of a pair.

of slide action bars 9s. The relative movement I of the slide and breech block for efiecting looking and unlocking of the breech block and positor strikes the end of the barrel chamber.

tive retraction and release of the firing pin as described above is accomplished as follows:

From their rearmost position in the receiver in which the breech block and slide are in. substantially axial alignment and the lugs 18 and 82 of the breech block are located at the front ends of their respective apertures 88 and 89 in the slide, see Fig. 4, the slide and breech block will be moved forwardly together in the receiver by forward movement of the slide action bars 9A until the forwardly projectingend of the cartridge ejector t9 strikes the end of the barrel chamber.

Since the camming surfaces 58 and 59 of the breech block and ejector respectively are normally held in contact by the spring 60, the forward movement of the breech block is momentarily stopped when the forward end of the ejec- However, since the ,apertures 88 and as of the slide are free to move forward relative to their corresponding lugs on the breech block, the slide continues to move forwardly relative thereto.

During this relative movement of the slide and breech block, the breech. block is compelled to swing transversely in the receiver by the sliding of the lug 82 in the arcuate aperture 8% of the slide; simultaneously the breech block pivots about the forwardly projecting end of the ejector it, the front end of the breech block being guided by engagement of its lug F8 in the arcuate slot lit of the slide. As the breech block swings outwardly transversely, its cam surface 5% moves away from the normally abutting cam surface 5% of the ejector 55, whereupon the latter is freed from the breech block, as shown in Fig. 2, and slides rearwardly relative thereto. The forwardly projecting end of the ejector is thus brought flush with the front end of the breech block, whereupon the breech block is enabled to move forwardly in the receiver until its front end con tacts the end of the barrel chamber. In its foremost position in the receiver, the rear end of the breech-block has been swungoutwardly sumcient to engage its bevelled or cam surface 58 with a similarly bevelled surface $5 on the rear edge of the ejection aperture 29. The breech block is thus effectively locked in breech closing position, in which position the extractor hook 53 engages the rim of a cartridge case in the barrel chamber.

The slide is moved rearwardly in the receiver to open the breech and extract and eject a fired cartridge. As the slide begins to move back relative to the locked breech block, the cam surface it of the latter is swung inwardly away from engagement with the bevelled surface '95 of the ejection aperture 2t due to displacement of the areuate aperture 89 of the slide relative to the lug 82 of the breech block. As the breech block swings inwardly, its camming surface 54 is again brought into engagement with the cooperating cam surface 59 of the ejector. Inasmuch as the front end of the ejector abuts the barrel chamtraction. As the slide continues to move'rearwardly, the breech block i swung inwardly into axial alignment with the slide and thereafter the forward edge of the arcuate aperture 89 and the shoulder 92 of the recess 90 engage the corresponding lugs 82 of the breech block and finger 10 of the firing pin, whereupon the striking element 68 of the latter is withdrawn into the breech block and the breech block is carried back to its rearmost position in the receiver. The fired cartridge is held in the recess 64 on the face of the breech block by the extractor 03 until the breech block reaches its rearmost position in the receiver, whereupon the rear end 55' of the ejector 55 strikes the rear wall of the receiver driving the ejector forwardly as shown in Fig. 2a. Thereupon the notch 51 of the ejector, which is in engagement with the rim of the fired case at a point opposite the extractor 63, flips the case laterally out of the ejection aperture 29. The breech block and slide are then ready to repeat the breech closing, primary extraction and election portions either automatically or manually depending upon the means used to reciprocate the slide actuating arms 94.

Slide actuating mechanism An improved gas operated means for automatically reciprocating the slide arms 94 is shown in Figs. 11 to 15, inclusive.

Referring to Fig. 11, the gas cylinder 39 is shown provided with a slotted rear end 30' which is removably secured in the recess 38 in the front wall of the receiver by a pin 96 adapted to pro- J'ect transversely through aligning apertures 91 and 98 in the gas cylinder and walls of th recess. The front end of the gas cylinder is shown secured in position beneath the forward end of the barrel I5 by a suitable fastening means comprising a dove-tail connection which, as shown in Figs. 11, 12 and 14, consists of an enlarged substantially cylindrical head I at the forward end of the gas cylinder having laterally extending tenons I02 on its upper side adapted to slidingly engage in grooves I03 of a strap I04 which encircles the end of the barrel. Both the bottom portion of the strap and the tenon portion-of the cylindrical head I00 are apertured, as indicated in I05 and I06 respectively, and are adapted to be assembled on the barrel so that these apertures are in axial alignment with an aperture or gas port I01 drilled readily in the bottom of the barrel.

Suitable means for securing the strap and cylindrical head in proper assembled relationship on the barrel comprises a pin I08 having a drive fit in a hole I09 which is shown drilled transversely through the strap I 04 at a point thereon to intersect a recess in the bottom of the barrel.

The cylindrical head I00 is provided at its outer end with internal screw threads for threadedly securing a gas plug I I0 therein, the latter having a lrerfed end III so that it can be turned by a screw driver or coin. The gas plug is apertured on two intersecting diameters at substantially right angles to each other, as indicated at H2 and H3, and is provided in its rear end with a smooth bored recess hereinafter termed a piston cylinder II4 which is of appreciably smaller inside diameter than the inside diameter of the gas cylinder 39 and is connected by an axially drilled hole H5 to the intersecting diametrically drilled holes H2 and H3 of the gas plug IIO. An apertured washer H6 of fiber or other suitable material is shown seated in the head of the piston cylinder I I4.

As shown in Fig. 11, the piston cylinder H4 is in direct communication through apertures H5 and H3 of the gas'plug, apertures I06 and I05 of the dove-tail connection and the aperture I01 of the barrel with the bore of the barrel; moreover, it will be clear that; by turning the gas plug IIO, the alignment of the aperture I00 of the dove-tail connection with the apertures II2 or Ila of the plug may be altered so as to obtain either an unrestricted or partially restricted gas passage. In this manner, the gas pressure transmitted to the piston cylinder 4 may be readily controlled. 7

A piston slidable in the cylinder H4 is indicated generally at H1 and comprises a tubular rod provided with a piston head H8 having a gas tight fit with the walls of the piston cylinder II4. To provide for quick reduction in the gas pressure on the piston head, the cylinder I I4 and piston I I8 are relatively short, as shown, so that, after moving rearwardly a distance substantially equal to its own length, the piston head clears the walls of the piston cylinder H4 and enables an immediate escape of gas into the larger interior of the gas cylinder 38; The latter is provided with a plurality of gas escape ports IIQ, as shown in Fig. 1, which permit the gases to escape into the atmosphere. Suitable means for guiding the forward end of the piston rod H1 in the gas cylinder 39 during the reciprocating motion of the piston head II8 into and from the piston cylinder II4 comprises a pair of radially extending disk-like flanges I20 integral with or otherwise secured to the piston rod I I1 and adapted to slidingly engage the inner walls of the gas cylinder 39. The apertured fiber washer H6 is disposed in the piston cylinder between its head wall and the piston head II8 to dampen the forward thrust thereof.

The piston head I I 8 is held in its forward position in the piston cylinder H4 by a coil compression spring I22 mounted within the tubular piston rod I H. The forward end of the spring abuts the rear wall of the piston head H8 and its rear end abuts .a washer I 23 of fiber or other suitable material supported on a spring pilot. The latter comprises a cylindrical plug I24 fitted in the rear end 39' of the gas cylinder and secured therein by the transverse pin 96 which passes through aligned holes in the plug and in the walls of the recess 38 of the receiver. A spring guide means comprising a stem I25 is suitably secured at its rear end to the plug I24 and extends forwardly within the coils of the spring I22 substantially one-third the length of the gas cylinder.

The tubular piston rod 1 i provided at its rear end with a substantially cylindrical yoke member I26 which is formed integral therewith or otherwise fixedly secured thereon, as shown in Figs. 12 and 13. The yoke I28 comprises a pair of laterally extending substantially fiat rectangular ears I21, each provided at its outer extremity with a substantially vertical rectangular fin I28. The yoke is of a diameter to slide freely within the gas cylinder 39 and constitutes a guide for the rear end of the piston rod II1. To this end, the gas cylinder is provided with a pair of slots I29 which extend longitudinally in a horizontal plane from the rear end of the cylinder forwardly for substantially one-third of its length.

The rear end of these slots are open so as to enable the ears I21 of the yoke I26 to enter therein, the dimensions of the slots being such normal forward position in Fig. 16, which is characterized by a manually op-' as make a smooth sliding fit with the ears 127 or the yoke. The vertical fins I28 are located on the outside of the gas cylinder and are provided with bevelled serrated surfaces J30 which constitute finger grips for manually reciprocating the yoke and its piston rod ill in the gas cylinder. Each fin I28 is provided with a semi-circular recess I32 having an internally threaded hub I33, see Fig. 12, for pivotally supporting the forward apertured end of a slide action bar 98 which is secured in the recess I32 by a screw l3fl engaging in the threaded hub I33. The rear end of each slide action bar extends through and is guided in a rectangular aperture I35 formed in the front wall 36 of the receiver to one side of the gas cylinder, as shown in Figs. 11 and 15.

' Each action bar is adapted to be connected at its rear end to a corresponding side of the slide 83, and, to this end, each slide action bar is provided with a hook portion 94' corresponding substantially in shape to the hook construction Bl at each side of the slide 83 and adapted to be engaged therewith to reciprocate the slidein .the receiver.

A fore-end l36 is shown fixedly secured to the gas cylinder 39 by means of a pair oi set screws B31 and comprises a substantially cylindrical front end having a suitable hand grip section E38 and grooved longitudinally on its upper side to accommodate the bottom of the barrel. The rear end of the fore-end comprises an integral, bottom, rearwardly extending, member 539 which is substantially one-third of a circumference, as shown in Fig. 15, and has edges Mil which are suitably bevelled to enable convenient access to the finger grips 536 of the yoke 526. The rear end of the bottom extension E39 abuts the front wall 36 of thereceiver, as shown in Fig. 11. Be-

tween the lower surface of the barrel l5 and the upper surface of the gas cylinder 39 and extending longitudinally from the front wall of the receiver to the rear end or shoulder M2 of the substantially cylindrical-portion 836 of the fore-end is a suitably shaped filler block M3 consisting of wood or other suitable material secured to the top of the gas cylinder by a pair of set screws lid.

The gun is first made ready for firing by grasping the finger grips lit and drawing the yoke rearwardly, thereby manually opening the breech. On releasing the finger grips, the breech block will be driven forwardly by the force of the compressed spring l2? into locked position in the receiver, a cartridge being automatically fed into the chamber by the advancing breech block. When the first cartridge is fired, a portion of the gas developed in the bore of the barrel by the burning powder passes down through the barrel gas port Nil into the piston cylinder ti l, thereby driving the piston rod ill rearwardly in the.

gas cylinder 39 against the resisting force of the coil spring l22. As the piston rod moves rearwardly, the yoke iZG slides rearwardly in the slots 829 of the gas cylinder. The breech block and slide are thereby driven to the rear end of the receiver simultaneously extracting and electing the fired cartridge in the manner-already described above. After the gas pressure has been expended by escape through the apertures N9 of the gas cylinder 39, the force of the compressed spring I22 returns the piston rod to its the cylinder, thereby automatically. loading a new cartridge in the chamber and locking the breech block in chamber closing position in the receiver.

A modification of the gas operated firearm, shown in Fig. 1, is a converted model, shown in erated action. To convert the gas operated gun to the manually operated gun, it is necessary simply to remove the barrel l5 and gas cylinder 39-fro1n the receiver l6 and substitute therefor the barrel and fore-end construction shown in Fig. 16.

It will be noted that the barrel E5 of the manually operated gun has no gas port and that a dummy gas cylinder 3! considerably shorter than the gas cylinder 39 of the gas operated gun i mounted beneath the barrel l5 to provide a support for the reciprocating fore-end 636'. The rear end of the dummy gas cylinder 39! is secured in the recess 38 of the receiver as in the above described manner while its front end is securely supported beneath the barrel l5 by a well known type of strap Hi6.

The slide action bars 9 are articulatively connected to the rear end of the reciprocating foreend 536' and hook into the slide as in the gas operated model described above, whereby manual reciprocation of the fore-end ltd operates the action in substantially the same manner.

It will be manifest from the above description and the drawings that the improved rifle of this invention has a smooth streamlined appearance and is readily convertible, selectively, from a fully automatic gas operated gun to a manually operated slide action gun; moreover the action possesses new and improved primary extraction characteristics which enable easy extraction and ejection of even the most severely stuck cases. And further, by providing the improved fore-end, shown on the gas operated gun, the finger grips of the manually operable slide are readily accessible and yet, in efiect, recessed into the rear end of the fore-end so as to constitute no hazard to the shooter during automatic operation of the breech block.

What is claimed is:

1. In a firearm, the combination with a receiver having fire control mechanism, a barrel, and a reciprocable slide; means for reciprocating said slide; a breech block movably mounted on said slide constructed and arranged to be moved laterally in said receiver by relative movement of said slide and breech block; a cartridge ejector; and means on said breech block adapted to cooperate with said ejector during lateral movement of said breech block to displace said breech block longitudinally in said receiver.

2. In a firearm, the combination with a receiver having fire control mechanism, 'a barrel, and a reciprocable slide; means for reciprocating said slide; a breech block movably mounted on said slide constructed and arranged to be moved laterally in said receiver by relative movement of said slide and breech block, said breech block having a longitudinal slot; a cartridge ejector; means for securing said ejector in said slot; and means on said breech block adapted to cooperate with said ejector during lateral movement of said breech block to displace said breech block longitudinally in said receiver.

3. In a firearm, the combination with a resaid ejector; and means on said breech block adapted to engage said projection during lateral movement of said breech block to displace said breech block longitudinally in said receiver.

4. In a firearm, the combination with a receiver having fire control mechanism, a barrel, and a reciprocable slide; means for reciprocating said slide; a breech block movably mounted on said slide constructed and arranged to be moved laterally in said receiver by relative movement of said slide and breech block, said breech block having a longitudinal slot and a recess in said slot; a cartridge ejector; means for securing said ejector for longitudinal movement in said slot; a lug on said ejector displaceable in said recess and having a cam surface; and a cam surface on one wall of said recess adapted to engage the cam surface 01 said ejector during lateral movement 01 said breech block to displace said breech block longitudinally in said receiver.

5. In a firearm, the combination with a receiver having fire control mechanism, a barrel, and a reciprocable slide; a breech block movably mounted on said slide; means for reciprocating said slide; means associated with said slide and breech block constructed and arranged to move said breech block laterally in said receiver by relative movement of said slide and breech block; a cartridge ejector carried on said breech block; and means on said breech block constructed and arranged to cooperate with said ejector during lateral movement of said breech block to enable primary extraction of a cartridge from the chamber of said barrel.

6. In a firearm, the combination with a receiver having fire control mechanism, a barrel, and a reciprocable slide; means for reciprocating said slide; a breech block movably mounted on said slide; means associated with said slide and breech block to move said breech block laterally in said receiver by relative movement of said slide and breech block; a cartridge extractor on said breech block; a cartridge ejector on said breech block opposite said cartridge extractor; breech block camming means on said ejector; and camming means on said breech block adapted to engage the breech block camming means of said ejector during lateral movement of said breech block to move said breech block rearwardly in said receiver whereby said extractor is enabled to withdraw a fired cartridge from the chamber of said barrel.

7. In a firearm, the combination with a receiver having fire control mechanism, a barrel, a cartridge ejection aperture, and a reciprocable slide, said slide having a pair of slots therein adjacent opposite ends thereof respectively; means for reciprocating said slide; a breech block movably mounted on said slide; projections on said breech block adjacent opposite ends thereof adapted to engage in the slots of said slide whereby relative movement of said slide and breech block moves said breech block laterally in said receiver; and means on said breech block adapted to be engaged inthe ejection aperture of said receiver by the lateral movement of said breech block to block said breech block in chamber closing position.

8. In a firearm; the combination with a receiver having fire control mechanism, a barrel, a cartridge ejection aperture, and a reciprocable slide, said slide having an open arcuate slot at its forward end and a closed arcuate slot adjacent its rear end means for reciprocating said slide; a breech block movably mounted on said slide; a pain of lugs projecting from said breech block adjacent opposite ends thereof to engage in the arcuate slots respectively of said slide whereby relative movement of said slide and breech block displaces at least one projection of said breech block laterally with respect to said slide; and a shoulder on said breech block adapted to engage a shoulder of said ejection aperture by the lateral movement of said breech block to lock said breech block in chamber closing position.

CRAWFORD C. LOOMIS.

CERTIFICATE OF CORRECTION.

Patent No. 2, 577,705.

June 5, 9M

CRAWFORD C. LOOHIS.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 6, second column, line 214., claim 7, for "block" second occurrence,read "lockline 51, claim 8, after "end" insert a semicolon; line 55, same claim, for

"pain" read -pa ir-- and that the said Letters Patent should'be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 25th day of December, A. D. 191;.5.

(Seal) Leslie Frazer First Assistant Commissioner of Patents. 

